Stop in for a cup of coffee

Check polarity. Fan running and blowing across your work? Whats gas set at? Porous welds can form due to various reasons. Dirty metal, incorrect gas flow
polarity set for solid wire using Argon 75% and Carbon is 25%. Gas flow is at 20 using 0.30 wire. No fan blowing across the weld and keeping the welding tip clean. Could it be a bad gas valve? I can hear the gas flow when I pull the trigger and pretty much clean metal. Think it might be me not having a steady hand is what I'm guessing.